It has been awhile since i last posted and it may be awhile longer yet before i post regularly again.
However i thought i would post some of our impressions of the SVS and Axiom sub, just not today.
Hopefully soon if i can get Bren (and others) to find some time for auditions.
Note the SVS is not mine but the owner will doing comparisons along with us.

_________________________"Those who preach the myths of audio are ignorant of truth."

Hey Chess - good to have you back. I think a lot ov people will be interested in the results. I expect the SVS to crush the EP350 in some respects but it'll be good to see what the little guy can do vs. the huge cylinder.

LOL, Sorry Thasp.
I've been so busy on a daily basis for months now that my time in the audio room has been limited. I was waiting on some information that just came in late this evening. I will finish the rather lengthy review and hopefully have it up by sometime tomorrow night (Wednesday at the latest, i swear). I did not even see the follow up posts to this thread until now.

I just received notice from Bren and sidvicious today, however they will not be available before i post the review. Hence the material will consist of the general ideas of 2 reviewers including myself and another friend. Note that he is not an Axiom owner.

If anyone wants some high resolution pictures of specific angles of these speakers, please let me know and i will try to post some when the text goes up.

On another note, my Anthem amp comes in tomorrow and the big Tannoys should be up and running again soon.

Edited by chesseroo (08/31/0401:44 AM)

_________________________"Those who preach the myths of audio are ignorant of truth."

The chance to review/audition the heralded SVS 16-46 PCi subwoofer was quite exciting. To pair it against the Axiom EP350 made things that much more fun.
I can sum up the review now in short words, but what fun would that be?

First ThoughtsWhen the SVS arrived, both my friend and I were humbled by the huge size. I had heard much about the large girth of these subs, but since they come in 3 different sizes, it was always hard to get a handle on just what version people were referring to. Since we received the largest of the 3, the PCi 16-46, it really was not difficult to relate the unit to a small water heater. The black (uggh, personal peeve) felt finish was reasonable for aesthetics, although for the first 2 nights I swore our cat was going to have a heyday with it. I don’t care who thinks the SVS subs are sexy, you just cannot beat the number or type of finishes available from Axiom or (insert other company here). I absolutely love the SVS SS wood finish but for nearly $2k USD I think I’ll stick with what we’ve got.
Axiom wins the aesthetics, hands down, across and under foot.

The SetupTo start off the listening session, the subwoofers were calibrated using the sub gain knobs and set as close to each other as possible near the same position that my EP350 previously sat. Both subs were connected via a simple y-splitter. The Onkyo DS797 receiver had the mains set to ‘small’ (when they were in use) to equalize any differences in manually setting a crossover on the units themselves. After the calibrations were complete, one of us would sit by the subs and alternate turning the SVS or Axiom sub on and off by flicking the power switches accordingly.
Although only two of us did the auditioning, I am waiting to hear back from Bren. Hopefully if his new Hsu sub has been purchased then some additions to this review can be made at that time.

We started off the listening with some simple test tones. From 4Hz up to the 125Hz range just to see what the subs were capable of doing. One simple conclusion drawn from the very first switch of the subwoofers was that there was absolutely no point in doing a blind test with the subs calibrated to the same SPL (75dB). Simply put, the SVS 16-46 subwoofer out rumbled the EP350 by about 3:1 (not an exaggeration) and hit the 16Hz with some audibility (67dB at 50% gain) while the EP350 seemed to struggle until 20Hz (64dB at 50% gain).
Was this particularly surprising?
Not really.
The SVS contains a 320W amplifier compared to the Axiom 200W and the cabinet size holds over double the volume (approximately 151 L vs. 77 L if my calculations are correct) with nearly the same diameter/depth and almost 3 times the height. A larger speaker will produce a larger sound given that all else remains similar. In this case, both subs are paired with 12” drivers and the SVS holds the spec for having a more powerful amp (1.6x if the specs are measured and reported in a similar manner).

At this point we had to decide what to do. Should we continue the audition with both subs set at equivalent SPL even though we knew the SVS was a dead giveaway each time? Or do we lower the gain on the SVS to a relatively equal value (by ear) and then try out some music and movies?
Well we ended up doing both actually. The ‘matched’ listening tests were done blind although after a couple of switches, we both realized that picking out the SVS from the Axiom was still ridiculously easy to do.

The ResultsBeginning with the easy tests, both subs were equalized at the same SPL (75dB). We started out by unplugging the main speakers and turning off all the rest in the receiver setup. After all, the best way to listen to a speaker is to eliminate all the rest and listen to just that one speaker. Integration with the set comes later.
So we proceeded with our usual test discs and heard how the SVS performed in music, followed by a couple of the usual test movies (U571, LOTR, Finding Nemo). Then we turned down the SVS gain to a point where it seemed to best ‘match’ the sub output from the EP350. When it was down about 5dB (35% gain vs. 45% on the Axiom) we decided that the levels were more equivalent. At this point we redid our evaluation of music and movie clips.
Next, we turned the main speakers back on and once again did the listening in both modes (equalized and then ‘matched’). After that was finished, we decided to really test out the SVS for fun and slowly cranked up the gain during some of the test movies to see how far it could be pushed. We also did this with the EP350 to see how far it could go in matching the SVS if at all.
Whew.
So, after we got through that, it was about 1AM and my wife (and sleeping baby girl) were not happy campers. I had to put it to rest.

The following week (this week past) I’ve had a chance to setup the SVS in the same way that I usually have my EP350, with the mains set to “large” and adjusting the SVS crossover to match the natural roll off of my Axiom M60s. I will comment more on that at the end of the summary.

Anyways, throughout the listening, both my friend and I drew similar, but not identical conclusions.

First and foremost, does the SVS “beat” the Axiom EP350?
As usual, the answer is, it depends.
It depends on personal preference.

For music I found the SVS to be overbearing at the 75dB calibration while my friend felt that the SVS was his cup of tea for right amount of bass. He did agree this was more dependant on a song-by-song basis and that at the 75dB calibration, the wall rattles were significantly taking away from the pleasure of music listening. At the lesser dB level (the ‘matched’ tests), the SVS was much more controlled and integrated better with the music but I still felt the bass notes tended to linger. The tall cylinder that was designed for a deep reach into the low Hz range lends to a lot more sound being reverberated within the room. It takes time for that sound to dissipate between beats and it is noticeable. Obviously room effects will come into play but we are comparing 2 subs in the same room with as close proximity as is physically possible.
On the upside, the taller SVS cylinder DOES reach into lower frequencies. This was noticeable with both the test tones and the organ music, far more so than with the EP350. My wife loves organ music so she was happy with hearing such a true note from the pipe organ. For dance music or anything designed with a strong beat, the SVS was just solid. It could handle the notes with ease and then some and it could certainly sound like a nightclub reproduction. Not a hint of port chuff for this beast.

On the flipside, there is the Axiom EP350. Very capable for hitting low notes in music, but without the obvious low extension of the SVS. The smaller cabinet made for a lesser boomy impact and was by far my preference for the majority of music. Bass did not linger and a twang from a bass viol did not rattle our chairs (about a 41Hz low note). The last time I sat next to a bass viol player I don’t quite recall my legs moving like Jell-O nor did I hear the loose wing nuts on my chair turning from vibration.

Now onto the movies. This one is simple. SVS kicks some serious rear end. There simply was no comparison to be made. The EP350 is capable of good rumble but the SVS is capable of realistic, down the road explosions.
Is this always necessary though? Absolutely not.
Anyone with a smaller room would be blown out with the use of this SVS. Overkill is definitely a word that could be used. For a larger space or for those who really want bass to hit them more in the chest, the SVS 16-46 HAS to be the choice here.

The test of the total SPL output was also a dead giveaway to the SVS. At 40% gain, the SVS made my stairs rattle while the EP350 could only do this around the 60% mark. The SVS at 60% made the stairs and 2 upstairs doors rattle while our 135lb Brazilian mastiff cowered from the thought of oncoming thunder. The EP350 never improved much beyond the 60% gain and the output sounded like it was on a down curve. But the SVS at 75% on the gain was still putting it out solid. At 80% we started to cut back and the output sounded like it was on its down curve around that point. With these thoughts in mind, we did a little test of the SPL levels. Using a 40Hz tone and putting both subwoofers at 75% gain, the SVS measured 85dB while the EP350 came in at 73dB. The SVS hit 73dB with a gain setting of only 50%!!
The toughest test scenes (LOTR Balins Tomb and the Darla tapping tank in Finding Nemo) were easily handled by the SVS even at 75% on the gain while the EP350 at 60% was back to its tendency for chuff although it was admittedly very hard to hear over the sound of the movie. I was becoming worried that during the movie scene while using the EP350 at 60%+ gain, it might start doing some kind of 30 year old washing machine rain dance. Just to note, it did not.
To handle bass notes of this magnitude, subwoofers need several key things including a lot of power (especially for smaller drivers), a solid cabinet and as large a driver as is feasible for plenty of air movement. The SVS weighing in at 60lbs compared to the EP350 39lb (along with previously mentioned factors) really makes a difference when some crazy bugger decides they want to hear live explosions in your basement through your stereo system. The two subwoofers were really not that close in some specifications and in reality a better comparison would have been the EP350 vs. the SVS 25-31 model.

A Problem?Overall I’m very impressed with the way the Axiom EP350 held up against the SVS PCi 16-46. I’m still working on integrating the SVS with my M60s in the same way that I have my EP350 typically setup. However, it seems that to get the level of bass I prefer for music, I have to turn down the SVS gain to 30% or a bit less, which for movies is too low, and hence the gain needs to be turned up again. This is just unacceptable for our daily uses which could swap between HT and music multiple times depending on who’s home. Two subwoofers would probably suit the situation better. Perhaps the EP350 for music and the SVS for HT while using just a wall switch for subwoofer power selection depending on the use any given day.

Our general summary:

For those looking for a music based sub, who are not into heavy beats, have a smaller room (e.g. no cathedral ceilings with a 17x40 living area leading into an open dining room and kitchen….2300 sq ft open floor, etc. etc.), listen to movies at moderate or lower volumes or require their speakers to be colour matched, then the Axiom EP350 (or EP175) is the unit of choice.
For those who like a bit more bass in ALL music, have a truly larger room or love to watch movies with sound up higher and explosions to be chest thumping, the SVS 16-46 should be the option of preference, otherwise consider this SVS model overkill. Compensating with the smaller models would probably make for an excellent trade off (slightly lesser bass but slightly lesser cost as well).

Just to note, the SVS cost $649 USD before shipping and taxes (just over $1000 Cdn after its arrival). The Axiom EP350 cost $620 with free shipping before taxes (about $934 Cdn new after arrival). One can easily understand why the SVS subwoofers have a good corner on the sales market. This sub is definitely worth multiple thumbs up for its price to performance ratio.

Now if they only started selling them in some wood vinyl finishes…

Edited by chesseroo (09/01/0412:03 AM)

_________________________"Those who preach the myths of audio are ignorant of truth."

The one thing that surprised me was the tube effect on the sub, that the notes lingered. I never knew that they effected the performance like that, and thought that the tube subs were downright superior to box subs. Boxes do have some advantage, and I wonder if the HSU tubes have the same lingering effects as the SVS. Is it brand specific, or is it a law of physics thing? A question for another day, and another comparison, I suppose.